Trying to transition from FT to PT - why am I not getting interviews?

I've worked at my current job for over a year. I work as a para in an elementary school with children with autism. Prior to this job I have a few years of experience working with adults with autism but before that I worked mostly in retail and food service jobs. I want to transition to part time work because I would like to focus on school and my art business.

I've been applying to a lot of retail jobs and food service but no one has contacted me. Is it because I currently work in a different field? Or am I doing something wrong? I have pretty much my entire work history from the last 5 years on my resume.

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